ISCC Metadata¶

iscc-jsonld¶

The ISCC JSON-LD Context and JSON Schema reference

@context¶

ISO 24138:2024

Name	Type	Default	Definition
@context	`string-uri`	http://purl.org/iscc/context	The JSON-LD Context URI for ISCC metadata.

@type¶

ISO 24138:2024

Name	Type	Default	Definition
@type	`string`	CreativeWork	The type of digital content according to schema.org classes (TextDigitalDocument, ImageObject, AudioObject, VideoObject).

$schema¶

http://purl.org/iscc/terms/#$schema ISO 24138:2024 Status: draft

Name	Type	Default	Definition
$schema	`string-uri`	http://purl.org/iscc/schema	The JSON Schema URI for ISCC metadata.

iscc-minimal¶

Minimal required ISCC Metadata

Example

{
  "@context": "http://purl.org/iscc/context",
  "@type": "CreativeWork",
  "$schema": "http://purl.org/iscc/schema",
  "iscc": "ISCC:KACYPXW445FTYNJ3CYSXHAFJMA2HUWULUNRFE3BLHRSCXYH2M5AEGQY"
}

iscc¶

http://purl.org/iscc/terms/#iscc ISO 24138:2024 Status: stable

Name	Type	Default	Definition
iscc	`string`	none	An ISCC-CODE in canonical representation. A valid ISCC Metadata object should include at least one of the `iscc`, `iscc_id`, or `iscc_code` fields. Example: `ISCC:KACYPXW445FTYNJ3CYSXHAFJMA2HUWULUNRFE3BLHRSCXYH2M5AEGQY`

iscc-basic¶

Basic user presentable ISCC Metadata essential for Meta-Code and Meta-Hash generation.

Example

{
  "@context": "http://purl.org/iscc/context",
  "@type": "VideoObject",
  "$schema": "http://purl.org/iscc/schema",
  "iscc": "ISCC:KACYPXW445FTYNJ3CYSXHAFJMA2HUWULUNRFE3BLHRSCXYH2M5AEGQY",
  "name": "The Never Ending Story",
  "description": "a 1984 fantasy film co-written and directed by *Wolfgang Petersen*"
}

name¶

http://schema.org/name ISO 24138:2024 Status: stable

Name	Type	Default	Definition
name	`string`	none	The title or name of the intangible creation manifested by the identified digital content. Used as input for ISCC Meta-Code generation. Example: `The Never Ending Story`

description¶

http://schema.org/disambiguatingDescription ISO 24138:2024 Status: stable

Name	Type	Default	Definition
description	`string`	none	Description of the digital content identified by the ISCC. Used as input for ISCC Meta-Code generation. Any user presentable text string (including Markdown text) indicative of the identity of the referent may be used. Example: `a 1984 fantasy film co-written and directed by Wolfgang Petersen`

meta¶

http://purl.org/iscc/terms/#meta ISO 24138:2024 Status: stable

Name	Type	Default	Definition
meta	`string`	none	Subject, industry, or use-case specific metadata encoded as Data-URL. Example: `data:application/json;charset=utf-8;base64,eyJleHRlbmRlZCI6Im1ldGFkYXRhIn0=`

iscc-embeddable¶

Metadata intended to be embedded into the media asset.

creator¶

http://schema.org/creator Status: draft

Name	Type	Default	Definition
creator	`None`	none	An entity primarily responsible for making the resource. Example: `Agatha Christie`

license¶

http://schema.org/license Status: stable

Name	Type	Default	Definition
license	`string-uri`	none	URI of license for the identified digital content. Example: `https://example.com/license-terms-for-this-item`

acquire¶

http://schema.org/acquireLicensePage Status: stable

Name	Type	Default	Definition
acquire	`string-uri`	none	This field must contain a valid URL referring to a page showing information about how one can acquire a license for the item. This may be a page of a web shop or NFT marketplace ready for providing a license. Example: `https://example.com/buy-license-for-item-here`

credit¶

http://schema.org/creditText Status: draft

Name	Type	Default	Definition
credit	`string`	none	A line of text that you expect users of the image (such as Google Images) to display alongside the image. Example: `Frank Farian - Getty Images`

rights¶

http://schema.org/copyrightNotice Status: draft

Name	Type	Default	Definition
rights	`string`	none	Contains any necessary copyright notice and should identify the current owner of the copyright of this work with associated intellectual property rights. Example: `© Copyright 2022 ISCC Foundation - www.iscc.codes`

iscc-extended¶

Extended ISCC Metadata

Example

{
  "@context": "http://purl.org/iscc/context",
  "@type": "TextDigitalDocument",
  "$schema": "http://purl.org/iscc/schema",
  "iscc": "ISCC:KACYPXW445FTYNJ3CYSXHAFJMA2HUWULUNRFE3BLHRSCXYH2M5AEGQY",
  "name": "The Neverending Story",
  "description": "a 1979 fantasy novel by German writer *Michael Ende*",
  "form": "Book",
  "image": "https://picsum.photos/200/300.jpg",
  "content": "https://example.com/the-asset.epub",
  "identifier": "urn:isbn:3-8273-7019-1",
  "creator": "Michael Ende",
  "license": "https://example.com/license.txt",
  "redirect": "https://example.com/about-the-asset"
}

media_id¶

http://purl.org/iscc/terms/#media_id Status: draft

Name	Type	Default	Definition
media_id	`string`	none	Vendor specific (internal) identifier for the source media file. Example: `05VQ3BGTGFCJA`

iscc_id¶

http://purl.org/iscc/terms/#iscc_id Status: stable

Name	Type	Default	Definition
iscc_id	`string`	none	The ISCC-ID of the digital content in canonical representation. A valid ISCC Metadata object should include at least one of the `iscc`, `iscc_id`, or `iscc_code` fields. Example: `ISCC:MAACAJINXFXA2SQX`

iscc_code¶

http://purl.org/iscc/terms/#iscc Status: stable

Name	Type	Default	Definition
iscc_code	`string`	none	A composite ISCC-CODE in canonical representation. Explicit alternative to the more compact `iscc` field. A valid ISCC Metadata object should include at least one of the `iscc`, `iscc_id`, or `iscc_code` fields. Example: `ISCC:KACYPXW445FTYNJ3CYSXHAFJMA2HUWULUNRFE3BLHRSCXYH2M5AEGQY`

image¶

http://schema.org/image Status: draft

Name	Type	Default	Definition
image	`string-uri`	none	URI for a user-presentable image that serves as a preview of the digital content. The URI may be a Data-URL RFC2397. If ISCC metadata is used as NFT metadata according to ERC-721 or ERC-1155 the URI should reference the actual digital content represented by the NFT. Example: `https://picsum.photos/200/300.jpg`

identifier¶

http://schema.org/identifier ISO 24138:2024 Status: draft

Name	Type	Default	Definition
identifier	`None`	none	Other identifier(s) referencing the work, product or other abstraction of which the referenced digital content is a full or partial manifestation.

content¶

http://schema.org/contentUrl Status: draft

Name	Type	Default	Definition
content	`string-uri`	none	URI of the digital content that was used to create this ISCC.

keywords¶

http://schema.org/keywords ISO 24138:2024 Status: stable

Name	Type	Default	Definition
keywords	`None`	none	Keywords or tags used to describe this content. Either a list of keywords or a string with comma separated keywords.

previous¶

http://purl.org/iscc/terms/#previous Status: draft

Name	Type	Default	Definition
previous	`string`	none	ISCC of the preceding version of this item.

form¶

http://schema.org/additionalType Status: draft

Name	Type	Default	Definition
form	`string`	none	The form or kind of content identified, using a Schema.org CreativeWork subtype. While `@type` provides a coarse modality classification (text, image, audio, video) and `mode`/`mediatype` describe technical aspects, `form` captures what the content is — a book, scholarly article, presentation, report, photograph, etc. Example: `ScholarlyArticle`

version¶

http://schema.org/version Status: draft

Name	Type	Default	Definition
version	`['integer', 'string']`	none	The version of the CreativeWork embodied by a specified resource.

tdm¶

http://purl.org/iscc/terms/#tdm Status: draft

Name	Type	Default	Definition
tdm	`object`	none	Machine-readable TDM reservation signals for AI-related content usage categories. Omitted fields indicate that the reservation status has not been determined.

genai¶

http://purl.org/iscc/terms/#genai Status: draft

Name	Type	Default	Definition
genai	`object`	none	Machine-readable generative AI disclosure signals for content transparency. Omitted fields indicate that the disclosure status has not been determined.

iscc-technical¶

Technical ISCC Metadata automatically inferred from the digital content by an ISCC Processor

Example

{
  "@context": "http://purl.org/iscc/context",
  "@type": "ImageObject",
  "$schema": "http://purl.org/iscc/schema",
  "iscc": "ISCC:KACYPXW445FTYNJ3CYSXHAFJMA2HUWULUNRFE3BLHRSCXYH2M5AEGQY",
  "filename": "the-file.png",
  "filesize": 46356,
  "mediatype": "image/png",
  "width": 640,
  "height": 480,
  "keywords": [
    "hashing",
    "identification"
  ]
}

mode¶

http://purl.org/iscc/terms/#mode Status: stable

Name	Type	Default	Definition
mode	`string`	none	The perceptual mode used to create the ISCC-CODE. Example: `video`

created¶

http://schema.org/dateCreated

Name	Type	Default	Definition
created	`string-date-time`	none	Datetime the ISCC was created for the item.

filename¶

http://purl.org/iscc/terms/#filename ISO 24138:2024 Status: stable

Name	Type	Default	Definition
filename	`string`	none	Filename of the referenced digital content (automatically used as fallback if the `name` field was not specified for ISCC processing)

filesize¶

http://schema.org/fileSize ISO 24138:2024 Status: stable

Name	Type	Default	Definition
filesize	`integer`	none	File size of media asset in number of bytes.

datasize¶

http://purl.org/iscc/terms/#datasize Status: draft

Name	Type	Default	Definition
datasize	`integer`	none	Size of the data processed for ISCC generation in number of bytes. Use this field when the ISCC is computed over data that is not a standalone file, such as an individual plane within a bioimage, a scene within a multi-scene container, or a data stream extracted from a composite format.

mediatype¶

http://schema.org/encodingFormat ISO 24138:2024 Status: stable

Name	Type	Default	Definition
mediatype	`string`	none	An IANA Media Type (MIME type) Example: `image/png`

duration¶

http://schema.org/duration ISO 24138:2024 Status: stable

Name	Type	Default	Definition
duration	`integer`	none	Duration of audio-visual media in seconds.

fps¶

http://purl.org/iscc/terms/#fps ISO 24138:2024 Status: stable

Name	Type	Default	Definition
fps	`number-float`	none	Frames per second of video assets. Example: `24`

width¶

http://purl.org/iscc/terms/#width ISO 24138:2024 Status: stable

Name	Type	Default	Definition
width	`integer-int32`	none	Width of visual media in number of pixels. Example: `640`

height¶

http://purl.org/iscc/terms/#height ISO 24138:2024 Status: stable

Name	Type	Default	Definition
height	`integer-int32`	none	Height of visual media in number of pixels. Example: `480`

characters¶

http://purl.org/iscc/terms/#characters ISO 24138:2024 Status: stable

Name	Type	Default	Definition
characters	`integer`	none	Number of text characters (code points after Unicode normalization) Example: `55689`

pages¶

http://schema.org/numberOfPages Status: draft

Name	Type	Default	Definition
pages	`integer`	none	Number of pages (for paged documents only) Example: `77`

language¶

http://schema.org/inLanguage ISO 24138:2024 Status: stable

Name	Type	Default	Definition
language	`None`	none	Language(s) of content BCP 47. Example: `en-US`

parts¶

http://purl.org/iscc/terms/#parts Status: draft

Name	Type	Default	Definition
parts	`array`	none	Indicates items that are part of this item via Content-Codes (inverse-property belongs).

part_of¶

http://purl.org/iscc/terms/#part_of Status: draft

Name	Type	Default	Definition
part_of	`array`	none	Indicates that this item is part of other items via their Content-Code.

features¶

http://purl.org/iscc/terms/#features Status: draft

Name	Type	Default	Definition
features	`array`	none	Granular features of the digital content.

units¶

http://purl.org/iscc/terms/#units Status: draft

Name	Type	Default	Definition
units	`array`	none	Individual ISCC-UNITs that make up a composite ISCC-CODE.

generator¶

http://purl.org/iscc/terms/#generator Status: draft

Name	Type	Default	Definition
generator	`string`	none	Name and version of the software that generated the ISCC

text¶

http://purl.org/iscc/terms/#text Status: draft

Name	Type	Default	Definition
text	`string`	none	Extracted plaintext of the digital content.

thumbnail¶

http://schema.org/thumbnailUrl ISO 24138:2024 Status: stable

Name	Type	Default	Definition
thumbnail	`string-uri`	none	URI of an autogenerated user-presentable thumbnail-image that serves as a preview of the digital content. The URI may be a Data-URL RFC2397. Example: `https://picsum.photos/200/300.jpg`

iscc-nft¶

Metadata for NFT Marketplaces

external_url¶

http://purl.org/iscc/terms/#external_url Status: draft

Name	Type	Default	Definition
external_url	`string-uri`	none	This is the URL that will appear below the asset's image on some NFT Marketplaces and will allow users to leave the site and view the item on your site. Supports URI template `(iscc-id)`.

animation_url¶

http://purl.org/iscc/terms/#animation_url Status: draft

Name	Type	Default	Definition
animation_url	`string-uri`	none	A URL to a multi-media attachment for the item.

properties¶

http://purl.org/iscc/terms/#properties Status: draft

Name	Type	Default	Definition
properties	`object`	none	Arbitrary properties. Values may be strings, numbers, object or arrays. Properties defined here may show up on NFT marketplaces. See ERC-1155 Example: `{'simple_property': 'example value', 'rich_property': {'name': 'Name', 'value': '123', 'display_value': '123 Example Value', 'class': 'emphasis', 'css': {'color': '#ffffff', 'font-weight': 'bold', 'text-decoration': 'underline'}}, 'array_property': {'name': 'Name', 'value': [1, 2, 3, 4], 'class': 'emphasis'}}`

attributes¶

http://purl.org/iscc/terms/#attributes Status: draft

Name	Type	Default	Definition
attributes	`array`	none	Similar to `properties` but as an array of objects. These attributes will show up on some NFT marketplaces. Example: `[{'trait_type': 'METAL', 'value': 'SILVER'}, {'display_type': 'number', 'trait_type': 'GENERATION', 'value': 1}]`

nft¶

http://purl.org/iscc/terms/#nft Status: draft

Name	Type	Default	Definition
nft	`string-uri`	none	A unique URI for a non-fungible token of the identified content. The URI must contain references to the blockchain, smart-contract and token. The recommended schemes are CAIP-22 and CAIP-29. Example: `eip155:1/erc721:0x06012c8cf97BEaD5deAe237070F9587f8E7A266d/771769`

iscc-crypto¶

Cryptography related ISCC Metadata

tophash¶

http://purl.org/iscc/terms/#tophash ISO 24138:2024 Status: draft

Name	Type	Default	Definition
tophash	`string`	none	A Multihash of the concatenation (binding) of metahash and datahash (default blake3). Example: `bdyqnosmb56tqudeibogyygmf2b25xs7wpg4zux4zcts2v6llqmnj4ja`

metahash¶

http://purl.org/iscc/terms/#metahash ISO 24138:2024 Status: stable

Name	Type	Default	Definition
metahash	`string`	none	A Multiformats multihash or IPFS CIDv1 of the supplied metadata. The hash is created from `name` and `description` fields or `meta` if supplied. Example: `f01551220b94d27b9934d3e08a52e52d7da7dabfac484efe37a5380ee9088f7ace2efcde9`

datahash¶

http://purl.org/iscc/terms/#datahash ISO 24138:2024 Status: stable

Name	Type	Default	Definition
datahash	`string`	none	A Multihash of the digital content (default blake3). Example: `bdyqk6e2jxh27tingubae32rw3teutg6lexe23qisw7gjve6k4qpteyq`

nonce¶

http://purl.org/iscc/terms/#nonce Status: draft

Name	Type	Default	Definition
nonce	`string`	none	Cryptographic nonce for replay protection. A 128-bit random value encoded as lowercase hexadecimal. Example: `0013a3c214c05796673503e6e549446d`

signature¶

http://purl.org/iscc/terms/#signature Status: draft

Name	Type	Default	Definition
signature	`object`	none	Cryptographic signature over ISCC metadata, conforming to the iscc-crypto signing protocol. Uses EdDSA (Ed25519) with JCS canonicalization.

iscc-declaration¶

Fields relevant in context with public ISCC declarations

original¶

http://purl.org/iscc/terms/#original Status: stable

Name	Type	Default	Definition
original	`boolean`	none	The signee of the declaring transaction claims to be the original creator of the work manifested by the identified digital content. Example: `True`

redirect¶

http://purl.org/iscc/terms/#redirect Status: stable

Name	Type	Default	Definition
redirect	`string-uri`	none	URL to which an ISCC resolver should redirect the ISCC-ID. Supports URI template `(iscc-id)` Example: `https://example.com/land-here-when-resolving-iscc-id`

chain¶

http://purl.org/iscc/terms/#chain Status: draft

Name	Type	Default	Definition
chain	`string`	none	The blockchain on which an ISCC-CODE is declared. Example: `ETHEREUM`

wallet¶

http://purl.org/iscc/terms/#wallet Status: draft

Name	Type	Default	Definition
wallet	`string`	none	The wallet-address that signs an ISCC declaration. Example: `0xb794f5ea0ba39494ce839613fffba74279579268`

credentials¶

https://www.w3.org/2018/credentials#VerifiableCredential Status: draft

Name	Type	Default	Definition
credentials	`None`	none	One or more Verifiable Credentials or one or more URIs pointing to one or more VCs. A reader of ISCC metadata must interpret the value according to the following rules If the value is a JSON `string` interpret it as an URI. The expectation is that the URI dereferences to a response with Content-type `application/json` where the data is a VC or an `array` of VCs. If the value is a JSON `object` interpret it as a VC according to the Verifiable Credentials JSON Schema. If the value is an `array` and an item in the `array` is a JSON `object` interpret it as a VC. If the value is an `array` and an items is a `string` interpret the item as an URI that dereferences to VC(s) Credentials should only be taken into account if the `credentialSubject` matches with the declarer (e.g. `did:pkh` representation of the declarers address). Example: `https://schema.iscc.codes/examples/vc.json`

verifications¶

http://purl.org/iscc/terms/#verifications Status: draft

Name	Type	Default	Definition
verifications	`array`	none	A list of self-verifications. Self-verifications are public URLs under the account/authority of the signee. The verification URL must respond to a GET request with text that contains a multihash of the ISCC declaration signees wallet address in the format of `verify:<multihash-of-wallet-address>:verify`. Example: `[{'url': 'https://twitter.com/titusz/status/1490104312051257347'}]`